A giant crane last night set about hauling the broken Airbus A320 jet from New York's Hudson river as investigators sought to pinpoint what had caused the near-disaster, from which all 155 people aboard the stricken plane escaped alive.

As details continued to emerge about the dramatic emergency landing of US Airways flight 1549 on Thursday, salvage experts prepared to remove the partially submerged body of the plane to an airfield, where it will be dismantled for clues as to what caused the engine malfunction.

Experts from the US National Transportation Safety Board will seek to retrieve the aircraft's black box to reveal the flight patterns, and confirm the pilot's call to air traffic control, made less than a minute after takeoff at New York's LaGuardia airport, that both engines had sucked in birds in a extremely rare case of "double bird strike".

However, the river's current is very fast, making it currently impossible for crews to hoist the aircraft out of the water and remove its flight data recorder and cockpit voice recorder.

The left engine, which passengers reported had burst into flames, has yet to be recovered from the bottom of the Hudson, having fallen off the body of the jet.

Experts said the wreckage could be nearly impossible to find because it is probably 30 feet to 50 feet down, stuck in mud and obscured by thick sediment, making conditions difficult for police and fire department divers.

Crash experts were last night interviewing the two pilots and three crew, as well as air traffic controllers.

New York meanwhile revelled in the details of an incident that for once in the city's troubled recent history ended happily.

Praise in particular was focused on the pilot, Captain Chesley Sullenberger, who managed to ditch a jet into one of the world's busiest waterways with all on board emerging safe and largely unharmed.

To recognise their bravery in landing the plane without loss of life the crew will be presented with the keys of New York City, the mayor, Michael Bloomberg, said yesterday.

The worst injury was believed to have been a woman passenger who suffered two broken legs. There were also cases of minor hypothermia. It was thought to be the first time for 45 years that a major aircraft crash-landed in water and every passenger on board made it out alive.

"Hemingway defined heroism once as grace under pressure and I think it's fair to say that Captain Sullenberger certainly displayed that yesterday," said the mayor of New York, Michael Bloomberg. "This is a story of heroes, something right out of a movie script."

Sullenberger had told passengers via the plane's intercom: "Brace yourself for a hard impact." Then he calmly put the aircraft down on the Hudson river. He was the last to leave the plane, walking the aisle twice to ensure nobody was left behind, according to Bloomberg.

"Sully", as Sullenberger is known, was not speaking publicly until after his interviews with crash investigators. His wife, Lorrie, made a brief statement outside her home in Danville, California. She said she had been overwhelmed by events, and was finding all the talk about her husband's heroism "a little weird".

"It was a shock. My husband has said over the years that it's highly unusual for a pilot to have any incidents in his career. I was stunned when he called to say there was an incident. Even then, I never thought he meant anything like this." She said he was a "pilot's pilot. He loves the art of the aeroplane".

Within seconds of taking off towards the north from LaGuardia, Sullenberger reported to air traffic control that both engines had been hit. He first requested to return to the airport, but then tried to land in a nearer commercial air strip just across the Hudson in New Jersey.

To reach the strip he banked sharply to the left at about 1,400 ft, following the course of the Hudson south along the west side of Manhattan and clearing the George Washington bridge by only about 800 ft.

By now the plane was without power, and Sullenberger's training as a certified glider pilot was coming into its own. He realised that he would not make it to the New Jersey strip, and decided to land on the water. He then executed what experts described as a perfect ditching of the plane.

He was the last to leave the plane, checking that everyone had left even as the aircraft began to lurch lower into the water.

Several survivors expressed their gratitude to Sullenberger. "That pilot - if he didn't get the recognition he needs," said Brad Wentzell. "He's the reason my two-year-old child still has a dad and my wife has a husband."

New witness accounts emerged of the jolt that passengers felt when they hit the water, followed by an eery silence as they tried to work out what was happening. Some panic broke out as water started rushing in towards the back of the plane, but it was quelled by a few passengers and the crew, who demanded calm.

The overwing escape doors were opened and passengers began filing out into icy water that instantly numbed legs. One of the rescue boat workers who rushed to the plane, Wilfredo Rivera, said "People were screaming. They thought they were going to die. They were saying, 'It's cold! The water's cold!'"

More than 100 of the passengers, apparently unfazed by what had happened to them, boarded another flight yesterday to their original destination, Charlotte in North Carolina. They were served free drinks during the flight and some were described as quite merry when they got there.

One urgent issue that the crash investigators will be looking into is whether jet engines are sufficiently protected from bird strikes. In the past two decades in the US about 80,000 incidents have been reported of birds hitting nonmilitary aircraft - a rate of about one strike for every 10,000 flights.

The investigating authorities say they will be studying what happened to the engines to see if anything needs to change.